Add GitHub workflows, test on PHP 8 (#31)

* Add GitHub workflows, test on PHP 8

* Reflect that package is not installable under PHP <5.6 due to deps

.github/workflows/ci.yaml

@@ -0,0 +1,60 @@
+# yamllint disable rule:line-length
+# yamllint disable rule:braces
+
+name: Continuous Integration
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+      - master
+
+jobs:
+  tests:
+    runs-on: ${{ matrix.operating-system }}
+
+    strategy:
+      matrix:
+        operating-system: ['ubuntu-latest']
+        php-version: ['5.6', '7.0', '7.1', '7.2', '7.3', '7.4', '8.0']
+
+    name: CI on ${{ matrix.operating-system }} with PHP ${{ matrix.php-version }}
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php-version }}
+          tools: composer:v2
+          coverage: none
+
+      - name: Get composer cache directory
+        id: composer-cache
+        run: echo "::set-output name=dir::$(composer config cache-files-dir)"
+
+      - name: Cache dependencies
+        uses: actions/cache@v2
+        with:
+          path: ${{ steps.composer-cache.outputs.dir }}
+          key: composer-${{ runner.os }}-${{ matrix.php-version }}-${{ hashFiles('composer.*') }}-${{ matrix.composer-flags }}
+          restore-keys: |
+            composer-${{ runner.os }}-${{ matrix.php-version }}-${{ hashFiles('composer.*') }}-
+            composer-${{ runner.os }}-${{ matrix.php-version }}-
+            composer-${{ runner.os }}-
+            composer-
+
+      - name: Install dependencies
+        run: |
+          composer update --no-interaction --prefer-dist --no-progress ${{ matrix.composer-flags }}
+
+      - name: Run tests
+        run: |
+          vendor/bin/phpunit
+
+      - name: Lint code
+        run: |
+          find Spreadsheet/ -type f -name \*.php | xargs -n1 php -l

composer.json

@@ -31,14 +31,15 @@
         }
     ],
     "require": {
-        "php": ">=5.3.3 <7.5",
+        "php": ">=5.6",
         "pear/ole": ">=1.0.0RC4",
         "pear/pear-core-minimal": "^1.10"
     },
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^2",
         "php-coveralls/php-coveralls": "^2.2",
-        "phpunit/phpunit": "<6.0"
+        "phpunit/phpunit": ">=5 <10",
+        "sanmai/phpunit-legacy-adapter": "^6 || ^8"
     },
     "autoload": {
         "psr-0": {

test/Test/Spreadsheet/Excel/Writer/WorkbookTest.php

@@ -6,7 +6,7 @@
  */
 class Test_Spreadsheet_Excel_Writer_WorkbookTest extends Test_Spreadsheet_Excel_WriterTestCase
 {
-    public static function setUpBeforeClass()
+    public static function doSetUpBeforeClass()
     {
         // Preload constants from OLE
         @class_exists(OLE::class);

test/Test/Spreadsheet/Excel/WriterTestCase.php

@@ -4,7 +4,7 @@
  * @author stev leibelt <artodeto@bazzline.net>
  * @since 2016-01-17
  */
-class Test_Spreadsheet_Excel_WriterTestCase extends PHPUnit_Framework_TestCase
+class Test_Spreadsheet_Excel_WriterTestCase extends \LegacyPHPUnit\TestCase
 {
     const FIXTURES_PATH = 'test/fixture/';